Perform backup on website files is important as to ensure users have a clean backup stored in local device. It is very useful for future purposes. 

You can follow these steps to create a backup and store it on your device:-

1. Login to Plesk control panel
   
   
2. Under Websites & Domains, go to File Manager
   
   
3. On Home directory, click on httpdocs
   
   
4. Tick checkbox besides Name column to select all files to be compressed
   
   
5. Dropdown Archive and select Extract Files
   
   
6. Click OK to start extract process
   
   
7. Locate the extracted files and left click on the row of the file and choose Download
   
   
8. The file will be downloaded to your local device.
   
   

Then, you can proceed with backup database of the website and store in your local device as well.